Target (protein/gene name): Catalase-Peroxidase E.C Number: 1.11.1.21 NCBI Gene # or RefSeq#: NC_000962.3 PBD ID: 2CCA Organism: Mycobacterium Tuberculosis Etiologic Risk Group: n/a Disease Information: Mycobacterium Tuberculosis are bacteria that initiate the pulmonary disease Tuberculosis by their deposition into aerosol drops then onto lung alveolar surfaces. Mycobacterium were initially found in the soil but they soon evolved to live in mammals through the domestication of cattle who passed the evolved M.bovis to humans as M.tuberculosis. TB mortality and morbidity dropped in the 20th century due to vaccines and antibiotics developed against this disease. Tuberculosis is associated with coughing and chest pain. In developing countries TB still causes much suffering due to the lack of healthy living conditions, poverty, and an inferior quality of drugs. Mainly affecting the lungs and central nervous system TB can reach great severity if left untreated with stages worsening after coughing blood. Links: 1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC164219/
2. https://www.cdc.gov/features/tbsymptoms/index.html
Essentiality: Catalase-peroxidase is responsible for the activation of the antituberculosis antibiotic, isoniazid. The bifunctional enzyme oxidized electron donors like NADPH and protects M.tuberculosis against toxic reactive oxygen species such as hydrogen peroxide that contribute to its survival. The domain and activity is on the NH2 terminus and the function of the C-terminal end is unknown.
Link:
1. https://enzyme.expasy.org/EC/1.11.1.21
Assayed by adding cell extracts to H2O2 in K2HPO4. O-dianisidine was used for peroxidase and was added to a phosphate buffer and H2O2 in deionized water.
Materials and Reagents:
Catalase activity was assayed by adding 0.1 mL of cell extracts to 1.4 mL of freshly prepared 13.2 mM H2O2 in 0.05 M K2HPO4. The reaction was initiated by adding the enzyme its and when the H2O2 concentrations were greater it was added last enzyme activity was lost. The solution was mixed an a Gilford 2000 spectrophotometer was used to determine loss of absorbance. Peroxidase was determined by adding 0.01 mL of o-dianisidine to a 1.5 0.01 M phosphate buffer. H2O2 was added to this in deionized water.
The enzyme assay that contains all of these materials in it is worth $135.75.
Expression:
Catalase-peroxidase- katG gene is expressed in the organism Mycobacterium Tuberculosis at great levels. This gene is expressed with many mutations as well some of which result in the resistance to INH- Isoniazid a drug established for the treatment of tuberculosis. This gene and its high levels in this organisms causes it to be a major contributor to the emergence of multi-drug resistance in Mycobacterium tuberculosis treatment. This gene can be found in E.coli BL21 (DE3).
Transmembrane Bound Regions: There are 3-4 transmembrane bound helices
Fig 2. TMPred output graph for Catalase-Peroxidase
Target (protein/gene name): Catalase-PeroxidaseE.C Number: 1.11.1.21
NCBI Gene # or RefSeq#: NC_000962.3
PBD ID: 2CCA
Organism: Mycobacterium Tuberculosis
Etiologic Risk Group: n/a
Disease Information: Mycobacterium Tuberculosis are bacteria that initiate the pulmonary disease Tuberculosis by their deposition into aerosol drops then onto lung alveolar surfaces. Mycobacterium were initially found in the soil but they soon evolved to live in mammals through the domestication of cattle who passed the evolved M.bovis to humans as M.tuberculosis. TB mortality and morbidity dropped in the 20th century due to vaccines and antibiotics developed against this disease. Tuberculosis is associated with coughing and chest pain. In developing countries TB still causes much suffering due to the lack of healthy living conditions, poverty, and an inferior quality of drugs. Mainly affecting the lungs and central nervous system TB can reach great severity if left untreated with stages worsening after coughing blood.
Links:
1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC164219/
2. https://www.cdc.gov/features/tbsymptoms/index.html
Essentiality: Catalase-peroxidase is responsible for the activation of the antituberculosis antibiotic, isoniazid. The bifunctional enzyme oxidized electron donors like NADPH and protects M.tuberculosis against toxic reactive oxygen species such as hydrogen peroxide that contribute to its survival. The domain and activity is on the NH2 terminus and the function of the C-terminal end is unknown.
Link:
1. https://enzyme.expasy.org/EC/1.11.1.21
Druggable Target: Not available
Assayable Enzyme Target: http://jcm.asm.org/content/20/3/421.full.pdf
Assayed by adding cell extracts to H2O2 in K2HPO4. O-dianisidine was used for peroxidase and was added to a phosphate buffer and H2O2 in deionized water.
Materials and Reagents:
Catalase activity was assayed by adding 0.1 mL of cell extracts to 1.4 mL of freshly prepared 13.2 mM H2O2 in 0.05 M K2HPO4. The reaction was initiated by adding the enzyme its and when the H2O2 concentrations were greater it was added last enzyme activity was lost. The solution was mixed an a Gilford 2000 spectrophotometer was used to determine loss of absorbance. Peroxidase was determined by adding 0.01 mL of o-dianisidine to a 1.5 0.01 M phosphate buffer. H2O2 was added to this in deionized water.
The enzyme assay that contains all of these materials in it is worth $135.75.
Link to Brenda: https://www.brenda-enzymes.org/enzyme.php?ecno=1.11.1.21&Suchword=&reference=&UniProtAcc=&organism%5B%5D=Mycobacterium+tuberculosis&show_tm=0
Structure:
Image of Protein:
Fig 1. Structure of 2CCA and S315T mutant from Mycobacterium tuberculosis
Pairwise alignment of BlastP:Query Coverage: 100%
Max % Identities: 100%
% Positives: 100%
Chain used for Homology: A
Similarity to Human: No significant similarity was found to show any results
Inhibitors: None
Link: http://www.bindingdb.org/bind/tabLuceneResult.jsp?thisInput=Catalase+peroxidase&submit=Go
Expression:
Catalase-peroxidase- katG gene is expressed in the organism Mycobacterium Tuberculosis at great levels. This gene is expressed with many mutations as well some of which result in the resistance to INH- Isoniazid a drug established for the treatment of tuberculosis. This gene and its high levels in this organisms causes it to be a major contributor to the emergence of multi-drug resistance in Mycobacterium tuberculosis treatment. This gene can be found in E.coli BL21 (DE3).
Transmembrane Bound Regions: There are 3-4 transmembrane bound helices
Fig 2. TMPred output graph for Catalase-Peroxidase
Links:
https://www.ncbi.nlm.nih.gov/pubmed/28743650
https://embnet.vital-it.ch/cgi-bin/TMPRED_form_parser
Gene Available:
https://www.atcc.org/Search_Results.aspx?dsNav=Ntk:PrimarySearch%7cgenomic+dna+mycobacteium+tuberculosis%7c3%7c,Ny:True,Ro:0,N:1000552&searchTerms=genomic+dna+mycobacteium+tuberculosis&redir=1
CDS Gene Sequence:
Protein Sequence: